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Homework Help: Absolute p

  1. Sep 4, 2006 #1
    to get the absolute pressure of a fluid you would take the static pressure and add it to the dynamic pressure. And you would have the total pressure. If that total pressure lets say 10psi static pressure and 5 psi dynamic pressure, gave a total of 15psi. So if you had 15 psi flowing through a pipe and into a closed tank to pressurize it would the value of the pressure in the closed tank be equal to 15psi the absolute pressure of the fluid?
  2. jcsd
  3. Sep 4, 2006 #2


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    The absolute pressure depends on the ambient pressure. In the earths atmosphere, at sea level, the ambient pressure is 1 atm or 14.696 psia. In a pipe, if there is flow, there is some pressure differential. If the outlet is at ambient pressure then one simply adds the differential pressure to ambient pressure to get local pressure.

    If there is a column of water open at the top, the pressure at top is ambient and increases as depth increases.

    One can talk of absolute pressure, or gage pressure, which is given by subtracting the ambient pressure from the absolute pressure.

    Sealed loops usually contain an accumulator or 'pressurizer' with which to control pressure by regulating the temperature of the vapor phase, or pressure valves.
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